Hi greg,
On 3/17/22 12:07, Steffen Eiden wrote:
Hi greg,
On 3/17/22 10:59, Greg KH wrote:
On Thu, Mar 17, 2022 at 09:47:06AM +0000, Steffen Eiden wrote:
This patch adds a new miscdevice to expose some Ultravisor functions to userspace. Userspace can send IOCTLs to the uvdevice that will then emit a corresponding Ultravisor Call and hands the result over to userspace. The uvdevice is available if the Ultravisor Call facility is present. Userspace can call the Retrieve Attestation Measurement Ultravisor Call using IOCTLs on the uvdevice.
The uvdevice will do some sanity checks first. Then, copy the request data to kernel space, build the UVCB, perform the UV call, and copy the result back to userspace.
Signed-off-by: Steffen Eiden seiden@linux.ibm.com Reviewed-by: Janosch Frank frankja@linux.ibm.com
Do you have a pointer to the userspace code that interacts with this kernel driver? That would be good to have to verify that the api here is sane.
There is a userspace tool currently under development, however, not yet ready to be published. Currently, I can only point to the Kselftest in this series and the kvm-unit-tests at https://lore.kernel.org/linux-s390/20220203091935.2716-1-seiden@linux.ibm.co...
I forgot to point out that the Attestation userspace tool will be open-source and included in the s390-tool package. I can send you the current state of that tool in private if you want.
thanks,
greg k-h
steffen
steffen